Metallurgical and mechanical characterisation of titanium based materials for endosseous applications obtained by selective laser melting

Abstract

The aim of the present work was to estimate the feasibility of selective laser melting (SLM) to produce Ti-hydroxyapatite bioactive composite materials for personalised endosseous implants. Mixtures of Ti6Al7Nb surface conditioned powder with hydroxyapatite up to 5 vol.-% were processed by SLM with the same scanning strategy and laser power in the range of 50–200 W. Specimens with porous structures were characterised from a structural and mechanical point of view. Irrespective to the initial hydroxyapatite content, density increased by increasing the laser power. The microstructure of manufactured parts mainly consisted of α′ martensite. In materials with 5 vol.-% hydroxyapatite, a phosphorous containing phase formed as a consequence of hydroxyapatite decomposition and interaction with the base Ti alloy. By increasing the laser power, the tensile strength increased mainly due to the density improvement of all the investigated materials.

Keywords:

• Titanium alloy
• Hydroxyapatite
• Selective laser melting
• Microstructure
• Tensile properties

T. Marcu and M. Todea wish to thank the project ‘Progress and development through post-doctoral research and innovation in engineering and applied sciences – PRIDE – contract no. POSDRU/89/1·5/S/57083’, co-funded from the European Social Fund through Sectorial Operational Program Human Resources 2007–2013. The research was carried out within the BIOMAPIM project, financed by the Romanian National Council for the Higher Education Scientific Research. Special thanks to the Metallurgy Research Group (Department of Materials Engineering and Industrial Technologies, University of Trento, Italy) headed by Professor A. Molinari, where a part of the research was carried out.

Notes

This paper is part of a special issue on ‘Euromat 2011: powder synthesis and processing for controlled microstructure’